After releasing SQL Server 2005 SP4 on Friday (you can read more about it here), the release services team did not hang up their hats for the Christmas holiday, but continued working on other releases. KB #2438344 : Cumulative update package 13 for SQL Server 2005 Service Pack 3This brings your SQL Server 2005 SP3 build number to 9.00.4315
KB ...

Yes, the day has finally arrived, and a couple of weeks ahead of schedule. Typically when Microsoft promises a release in Qx or Hx, the software comes on the last or second last day of that quarter or half. This year, we get an early Christmas present: SQL Server 2005 SP4.
Downloads
To download SP4, go to this ...

Today Microsoft has released two updates for SQL Server. Listed below are the two updates, the blog posts from the SQL Server Release Services team, and the KB articles where you can read about the fixes and request downloads.
SQL Server 2005 SP3 Cumulative Update #12 ...